Opium
Opium, narcotic drug produced from the drying resin of unripe capsules of the opium poppy , Papaver somniferum. Opium is grown mainly in Myanmar (formerly Burma) and Afghanistan. The legitimate world demand for opium amounts to about 680 metric tons a year, but many times that amount is distributed illegally. In its commercial form, opium is a chestnut-colored globular mass, sticky and rather soft, but hardening from within as it ages. It is processed into the alkaloid morphine which has long served as the chief painkiller in medical practice, although synthetic substitutes such as meperidine (trade name Demerol) are now available. Heroin, a derivative of morphine, is about three times more potent. Codeine is another important opium alkaloid. The molecules of opiates have painkilling properties similar to those of compounds called endorphins or enkephalins produced in the body. Being of similar structure, the opiate molecules occupy many of the same nerve-receptor sites and bring on t...